The invention relates to a process for manufacturing a thin strip or foil of aluminum which, after a recrystallizing final anneal, exhibits mainly cube texture.
In aluminum the so called cube orientation often occurs as a texture component after recrystallization has taken place. The fraction of cube texture greatly depends, however, on impurity or alloying elements, rolling and annealing procedures, and on the thickness of the thin strip or foil.
To achieve the maximum possible fraction of cube orientation in foils or strips thinner than 0.2 mm it has been proposed, after hot rolling, to cold roll the metal to a thickness of 1.05 to 1.35 times the final thickness, the thickness after hot rolling being at least 11 times this intermediate thickness. The metal is then to be annealed, at this intermediate thickness, at temperatures between 180.degree. and 350.degree. C. before cold rolling to final thickness. At final thickness a recrystallizing anneal is then carried out at temperatures between 300.degree. and 650.degree. C.
The amount of cube texture reported from this treatment is 45-95% for 99.993% aluminum and 70% for 99.96% aluminum. The essential point of this process that is, the small degree of cold reduction from the intermediate thickness to the final thickness, has the effect, however, of significantly increasing manufacturing costs.
The object of the present invention is therefore to develop a process for producing a larger fraction of cube texture in aluminum thin strip and foil such that the said process provides similar or even better results at lower expense.